A noble metal separator and method

Abstract

The present application belongs to the technical field of metallurgy, and particularly relates to a noble metal separator and method. The present application generates liquid cinder and acid raw material gas by oxidizing pyrite; then reduces the liquid cinder to make the high-valence oxide in the liquid cinder react to generate FeO and coal gas; finally, the reduced liquid cinder is flushed in a precipitation separation container by using a flushing agent in a molten state with a density greater than that of the liquid cinder, so that the noble metal is saturated in the flushing agent and then precipitates and separates. The present application simplifies the extraction steps of noble metal, significantly improves the extraction efficiency of noble metal in pyrite, and the whole process can be controlled by the flushing speed of the flushing agent, so that the quality is controllable.

Description

Technical Field

[0001] This invention belongs to the field of metallurgical technology and relates to a precious metal separator and method. Background Technology

[0002] Pyrite is used as a raw material for the industrial production of sulfuric acid. Pyrite is roasted in a fluidized bed furnace to produce sulfuric acid feed gas and slag. The slag contains about 55% iron and also contains approximately 1.3 g / t of gold and 15 g / t of silver. Currently, the slag is used as an iron-containing raw material in ironmaking. During the ironmaking process, gold and silver enter the molten iron. However, the content of gold and silver in the molten iron does not reach saturation, so the gold and silver cannot be recovered, resulting in huge waste.

[0003] Chinese patent document CN102586618A (201210095263.6) discloses a smelting process for pyrite. This process involves first smelting pyrite using an oxidative smelting method, producing matte enriched with precious metals, molten ferrous iron slag, and high-temperature flue gas containing SO2. The matte settles at the bottom of the furnace and is discharged. After separation from the molten ferrous iron slag, the molten ferrous iron slag is reduced and smelted in a reduction smelting furnace to produce pig iron. The discharged matte is used to recover precious metals, and the discharged high-temperature flue gas is used for waste heat recovery and acid production. While this technical solution can extract precious metals from pyrite, the matte-making process leads to incomplete combustion of the pyrite, resulting in a large amount of sulfur entering the molten ferrous iron slag. This results in the subsequently smelted iron having a high sulfur content and failing to meet quality standards. Summary of the Invention

[0004] The purpose of this invention is to provide a precious metal separator and method, which first oxidizes and reduces pyrite sequentially, and then uses a molten flushing agent to flush the reduced liquid slag in a precipitation separation container, so that the precious metals are saturated in the flushing agent and precipitated and separated, thereby improving the extraction efficiency of precious metals and allowing for effective control of the extraction process.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for separating precious metals, comprising the following steps: S1. The precious metals in pyrite include gold and silver. Pyrite is oxidized to produce liquid slag and acid-making feed gas. S2. Reduce the liquid slag to react the high-valence oxides in the liquid slag to generate FeO and coal gas; S3. The reduced liquid slag is rinsed in a sedimentation separation vessel using a molten rinsing agent with a density greater than that of the liquid slag, separating the precious metals from the liquid slag. The precious metals precipitate after being saturated in the rinsing agent. Because Fe2O3 reacts with the rinsing agent (Fe, Ag), it consumes a large amount of the rinsing agent. Therefore, this invention reduces Fe2O3 to FeO before extracting the precious metals.

[0006] Preferably, in step S1 of this invention, the acid-producing gas is used to prepare sulfuric acid; Preferably, in step S1, a solvent is added to lower the melting point and viscosity of the liquid slag; the solvent is selected from at least one of quartz, calcium oxide, limestone, fluorite, borax and bentonite.

[0007] Preferably, in step S3 of this invention, the rinsing agent is molten iron or molten silver. When the rinsing agent is molten iron, gold and silver dissolve in the molten iron, but are not soluble in the liquid slag, although they are dispersed in the slag. Using molten iron as the rinsing agent allows the precious metals dispersed in the liquid slag to be captured by the molten iron. The dispersed gold and silver enter the molten iron and flow together with it into the lower part of the rinsing ladle. The higher density of gold and silver further precipitates and separates from the molten iron, flowing into the bottom of the rinsing ladle.

[0008] When the rinsing agent is silver solution, gold dissolves in silver. Gold and silver are insoluble in liquid slag, but they are dispersed in the slag. Using silver solution as the rinsing agent allows the gold dispersed in the liquid slag to be captured by the silver solution. The dispersed gold enters the silver solution and enters the lower part of the rinsing bag together with the silver solution.

[0009] Preferably, in step S3 of this invention, the rinsing agent is recycled to reduce production costs.

[0010] The present invention also discloses a precious metal separator for performing the above-mentioned precious metal separation method, comprising a precious metal separator body, a flushing agent package, a vacuum machine, an inlet pipe check valve, and an outlet pipe check valve; The precious metal separator body is provided with a material distribution area and a rinsing separation area from top to bottom. The rinsing separation area is provided with a liquid slag layer, a rinsing agent layer and a precious metal precipitation layer from top to bottom. The flushing agent package is a closed container, with a gas zone and a flushing agent pool arranged from top to bottom. The flushing agent pool is used to hold the flushing agent. The gas zone is connected to the vacuum machine, the rinsing agent tank is connected to the fabric area through the inlet pipe, and the rinsing agent tank is connected to the rinsing separation zone through the outlet pipe; The inlet pipe and outlet pipe are respectively equipped with an inlet pipe check valve and an outlet pipe check valve; A vent valve is provided at the top of the gas zone.

[0011] Preferably, in this invention, two or more flushing agent packs are connected to the precious metal separator body, and at least two flushing agent packs are provided. The flushing agent packs work alternately to achieve uninterrupted flushing. When one flushing agent pack is vacuumed, it draws in the flushing agent, while the other flushing agent pack does not vacuum and discharges the flushing agent, thereby improving the extraction efficiency of precious metals.

[0012] Preferably, the fabric area is equipped with a flushing agent distributor, which is connected to the inlet pipe. The flushing agent distributor includes multiple flushing agent outlets distributed along the cross-section of the precious metal separator body. The flushing agent distributor allows the flushing agent to fall evenly into the liquid slag layer, thereby achieving uniform extraction of precious metals.

[0013] Preferably, the precious metal separator body is provided with a precious metal discharge port at the bottom, which is located in the precious metal precipitate layer and is used to periodically discharge precious metals.

[0014] Preferably, the precious metal separator body and / or flushing agent package are equipped with an electromagnetic induction heating device to keep the liquid in the flushing agent package and the precious metal separator body in a superheated state, so that it has good fluidity and prevents solidification after heat dissipation.

[0015] Preferably, the precious metal separator body is provided with a liquid slag inlet and outlet, which are connected to the liquid slag layer and are used for the replacement and discharge of liquid slag.

[0016] Compared with the prior art, the beneficial effects of the present invention are: This invention oxidizes pyrite to generate liquid slag and acid-producing gas. The liquid slag is then reduced, causing the high-valence oxides in the slag to react and generate FeO and coal gas, thus preventing the Fe2O3 in the liquid slag from reacting with the flushing agent. Finally, the reduced liquid slag is flushed in a sedimentation separation vessel using a molten flushing agent with a density greater than that of the liquid slag. The flushing agent separates gold and silver from the liquid slag, allowing the precious metals to precipitate after saturation in the liquid flushing agent. This invention simplifies the precious metal extraction process and significantly improves the extraction efficiency of precious metals from pyrite. Furthermore, the entire process can be controlled by adjusting the flushing speed of the flushing agent, achieving quality control. Attached Figure Description

[0017] Figure 1 This is a flowchart of the precious metal separation method of the present invention; Figure 2 This is a schematic diagram of the structure of the precious metal separator of the present invention; Figure 3 This is a schematic diagram of the flushing agent distributor of the present invention; In the figure, 1 is the precious metal separator body, 2 is the flushing agent pack, 3 is the vacuum machine, 4 is the inlet pipe check valve, 5 is the outlet pipe check valve, 6 is the vent valve, 7 is the flushing agent distributor, and 71 is the flushing agent outlet. 11 Fabric area; 12 Washing and separation area; 21 Gas Zone, 22 Flushing Agent Pool; 100 liquid slag layer, 200 flushing agent layer, 300 precious metal precipitation layer. Detailed Implementation

[0018] The technical solutions in the embodiments of the present invention will now be clearly and completely described in conjunction with the accompanying drawings.

[0019] Example 1 In this embodiment, in step S3, the rinsing agent is molten iron.

[0020] like Figure 1 As shown, a method for separating precious metals includes the following steps: S1. The precious metals in pyrite include gold and silver. Pyrite is oxidized to produce liquid slag and acid-making feed gas. The above combustion oxidation reaction can be carried out in an existing combustion furnace.

[0021] In step S1, a solvent is added to lower the melting point and viscosity of the liquid slag, which is beneficial for the separation of heavy metals in the flash slag; the solvent is selected from at least one of quartz, calcium oxide, limestone, fluorite, borax and bentonite. S2. Reduce the liquid slag to react the high-valence oxides in the liquid slag to generate FeO and coal gas; the above reduction reaction can be carried out in an existing reduction furnace.

[0022] S3. The reduced liquid slag is rinsed in a sedimentation separation vessel using a molten rinsing agent with a density greater than that of the liquid slag, separating the precious metals from the liquid slag. The precious metals are then saturated in the rinsing agent and precipitated. The specific structure of the sedimentation separation vessel is not specifically limited in this method.

[0023] In step S1, the acid-producing gas is used to prepare sulfuric acid.

[0024] In step S3, the rinsing agent can be recycled.

[0025] like Figure 2 As shown, a precious metal separation method for performing the precious metal separation method described in this embodiment includes a precious metal separator body 1, a flushing agent package 2, a vacuum machine 3, an inlet pipe check valve 4, and an outlet pipe check valve 5.

[0026] The precious metal separator body 1 is provided with a cloth feeding area 11 and a rinsing and separation area 12 from top to bottom. The rinsing and separation area 12 is provided with a liquid slag layer 100, a rinsing agent layer 200 and a precious metal precipitation layer 300 from top to bottom.

[0027] The flushing agent package 2 is a closed container, with a gas zone 21 and a flushing agent pool 22 arranged from top to bottom. The flushing agent pool 22 is used to hold the flushing agent.

[0028] The gas zone 21 is connected to the vacuum machine 3, the rinsing agent pool 22 is connected to the fabric zone 11 through the inlet pipe, and the rinsing agent pool 22 is connected to the rinsing separation zone 12 through the outlet pipe.

[0029] The inlet pipe and outlet pipe are respectively equipped with an inlet pipe check valve 4 and an outlet pipe check valve 5.

[0030] A vent valve 6 is provided at the upper part of the gas zone 21.

[0031] Two or more flushing agent packs 2 are connected to the precious metal separator body 1.

[0032] The fabric area 11 is equipped with a rinsing agent distributor 7, which is connected to the inlet pipe.

[0033] The lower part of the precious metal separator body 1 is provided with a precious metal discharge port.

[0034] The precious metal separator body 1 and the flushing agent pack 2 are equipped with an electromagnetic induction heating device. The electromagnetic induction heating device is used to maintain a certain degree of superheat in the liquid, which is beneficial to the flushing effect; the temperature is set to 1250℃-1400℃.

[0035] Characteristics of the relevant materials: Specific gravity: Gold: 19.32 t / m 3 Silver: 10.5 t / m 3 ; Cinder: 4t / m 3 ~5t / m 3 Iron: 7t / m 3 .

[0036] Melting point: Gold: 1064.43℃; Silver: 961.78℃; Slag: 1150~1250℃; Iron: 1150℃.

[0037] Working principle: Molten iron is poured into the precious metal separator body 1. The oxidized and reduced liquid slag flows in from one end of the precious metal separator body 1 and flows out from the other end. The precious metal separator body is divided into a liquid slag layer 100, a flushing agent layer 200, and a precious metal precipitation layer 300. The vent valve 6 above the flushing agent pack 2 is closed, and the vacuum machine 3 is turned on to evacuate the flushing agent pack 2. The molten iron in the precious metal separator body 1 flows into the flushing agent pack 2 through the connecting pipe. Then, the vent valve 6 is opened, and the molten iron in the flushing agent pack 2 flows into the flushing agent distributor 7 at the top of the precious metal separator body 1 through the pipe. The molten iron falls evenly and passes through the liquid slag layer 100. The molten iron and the liquid slag come into full contact, and the precious metals in the liquid slag are washed down by the molten iron and enter the flushing agent layer 200 together. The heavier precious metals further precipitate into the precious metal precipitation layer 300 below. The precious metals in the precious metal precipitation layer are periodically discharged, and then gold and silver are further refined.

[0038] To ensure uniform molten iron flow, the flushing agent distributor 7 in this embodiment includes multiple flushing agent outlets 71 distributed along the cross-section of the precious metal separator body 1. For example... Figure 3 As shown, the flushing agent distributor 7 is located at the top of the precious metal separator body, including a main pipe and multiple branch pipes connected to the main pipe. The multiple branch pipes are arranged horizontally along the cross-section of the precious metal separator body 1, and there are multiple flushing agent outlets on the branch pipes. The main pipe is connected to the inlet pipe.

[0039] The connecting pipe between the flushing agent pack 2 and the precious metal separator body 1 is equipped with an outlet pipe check valve 5 and an inlet pipe check valve 4. In this embodiment, at least two flushing agent packs are provided, which alternately suck and discharge for uninterrupted flushing. The molten iron consumed during the flushing process is replenished periodically.

[0040] The advantages of using molten iron as a cleaning agent are that molten iron is readily available and inexpensive.

[0041] Example 2 In this embodiment, in step S3, the rinsing agent is silver solution. Specifically, the precious metal separator body 1 is maintained at 1350°C, and the rinsing agent package 2 is maintained at 1150°C.

[0042] Working principle: Silver water is injected into the precious metal separator body 1. The oxidized and reduced liquid slag flows in from one end of the precious metal separator body 1 and flows out from the other end. The precious metal separator body is divided into a liquid slag layer 100, a flushing agent layer 200, and a precious metal precipitation layer 300. Close the vent valve 6 above the flushing agent pack 2, turn on the vacuum machine 3 to evacuate the flushing agent pack 2, and the silver liquid in the precious metal separator body 1 flows into the flushing agent pack 2 through the connecting pipe. Then open the vent valve 6, and the silver liquid in the flushing agent pack 2 flows into the flushing agent distributor 7 at the top of the precious metal separator body 1 through the pipe. The silver liquid falls evenly and passes through the liquid slag layer 100. The silver liquid and liquid slag come into full contact, and the precious metals in the liquid slag are washed down by the silver liquid and enter the flushing agent layer 200 and the precious metal precipitation layer 300 together (when using silver liquid as flushing agent, the flushing agent layer 200 and the precious metal precipitation layer 300 are integrated). A portion of the precious metals in the precious metal precipitation layer is periodically discharged, and then gold and silver are further refined.

[0043] To ensure uniform silver flow, the flushing agent distributor 7 in this embodiment includes multiple flushing agent outlets 71 distributed along the cross-section of the precious metal separator body 1. For example... Figure 3 As shown, the flushing agent distributor 7 is located at the top of the precious metal separator body, including a main pipe and multiple branch pipes connected to the main pipe. The multiple branch pipes are arranged horizontally along the cross-section of the precious metal separator body 1, and there are multiple flushing agent outlets on the branch pipes. The main pipe is connected to the inlet pipe.

[0044] The connecting pipe between the flushing agent pack 2 and the precious metal separator body 1 is equipped with an outlet pipe check valve 5 and an inlet pipe check valve 4. In this embodiment, at least two flushing agent packs are provided, which alternately suck and discharge for uninterrupted flushing. The silver solution consumed during the flushing process is replenished periodically.

[0045] Using liquid silver as a flushing agent is advantageous because gold and silver are highly miscible, resulting in high efficiency in capturing gold with silver. The disadvantage is that silver is expensive.

Claims

1. A method for separating precious metals, characterized in that, Includes the following steps: S1. The precious metals in pyrite include gold and silver. Pyrite is oxidized to produce liquid slag and acid-making feed gas. S2. Reduce the liquid slag to react the high-valence oxides in the liquid slag to generate FeO and coal gas; S3. The reduced liquid slag is rinsed in a sedimentation separation vessel using a molten rinsing agent with a density greater than that of the liquid slag, so that the precious metals are separated from the liquid slag and precipitated after the precious metals are saturated in the rinsing agent.

2. The precious metal separation method as described in claim 1, characterized in that: In step S1, the acid-producing gas is used to prepare sulfuric acid; Preferably, in step S1, a solvent is added to lower the melting point and viscosity of the liquid slag; the solvent is selected from at least one of quartz, calcium oxide, limestone, fluorite, borax and bentonite.

3. The precious metal separation method as described in claim 1, characterized in that: In step S3, the rinsing agent is molten iron or molten silver.

4. The precious metal separation method as described in claim 1, characterized in that: In step S3, the rinsing agent is recycled.

5. A precious metal separator for performing the precious metal separation method according to any one of claims 1 to 4, characterized in that, It includes a precious metal separator body (1), a flushing agent pack (2), a vacuum machine (3), an inlet pipe check valve (4), and an outlet pipe check valve (5); The precious metal separator body (1) is provided with a cloth area (11) and a rinsing and separation area (12) from top to bottom. The flushing agent pack (2) is a closed container, with a gas zone (21) and a flushing agent pool (22) arranged from top to bottom. The flushing agent pool (22) is used to hold the flushing agent. The gas zone (21) is connected to the vacuum machine (3), the rinsing agent pool (22) is connected to the fabric zone (11) through the inlet pipe, and the rinsing agent pool (22) is connected to the rinsing separation zone (12) through the outlet pipe; The inlet pipe and outlet pipe are respectively equipped with an inlet pipe check valve (4) and an outlet pipe check valve (5); A vent valve (6) is provided at the top of the gas zone (21).

6. The precious metal separator as described in claim 5, characterized in that: Two or more flushing agent packets (2) are connected to the precious metal separator body (1).

7. The precious metal separator as described in claim 5, characterized in that: The fabric area (11) is provided with a flushing agent distributor (7), which is connected to the inlet pipe. The flushing agent distributor (7) includes multiple flushing agent outlets (71) distributed along the cross-section of the precious metal separator body (1).

8. The precious metal separator as described in claim 5, characterized in that: The lower part of the precious metal separator body (1) is provided with a precious metal discharge port.

9. The precious metal separator as described in claim 5, characterized in that: The precious metal separator body (1) and / or flushing agent pack (2) are equipped with an electromagnetic induction heating device.

10. The precious metal separator as described in claim 5, characterized in that: The precious metal separator body (1) is provided with a liquid slag inlet and outlet.

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